Rice is the most widely distributed dietary staple in the world. It also makes up a significant percentage of global farm land; rice is farmed on about 160 million hectares of land each year, just behind corn (mostly used as animal feed) at about 175 million hectares, and wheat farmed on about 220 million hectares.
Rice has the highest extraction rate of any cereal, meaning when considering the fraction of each grain utilized to as food, rice produces more energy per hectare than any other cereal.
Total food protein per production hectare for rice is second only to wheat. However, when the superior quality of rice protein is considered, the yield per hectare of utilizable protein is actually higher for rice than for wheat.
On average, each hectare of rice farmed yields about 4.4 tons of paddy (unmilled rice); yields can vary greatly depending on local farming methods, seeds, and climate.
In recent years, global paddy production has been about 700 million tons, equivalent to about 470 million tons once the rice is milled.
Of the 470 million tons of milled rice produced each year, only about 38 million tons, or about 2% of global production is traded each year.
I. Rice Processing
While growing, rice starts out bright green and as the plant ripens it turns golden-yellow. Rice still in the hull is called paddy rice or rough rice. The paddy can be further processed to yield several products, including:
Brown rice : Rice which has had the outer husk removed through the milling process but the inner hull is left intact, accounting for the brown appearance, chewy texture, and higher nutrient and fiber content compared to white rice.
Parboiled rice : Rice which has been steamed and vacuumed dried before being de-hulled, infusing the nutrients from the hull into the rice and reducing its cooking time. Parboiled rice is especially popular in parts of South Asia, including Bangladesh and East India, Africa, and Brazil among other nations.
White rice : Rice which has had the inner and outer hulls removed along with the endosperm, and then polished.
Rice bran : A byproduct of the rice milling process, rice bran consists of the layer between the inner white rice grain and the outer hull along with the germ.
Rice bran oil : A byproduct of the rice milling process, rice oil is extracted from the rice germ and inner hull. It has a high smoke point and mild flavor. It’s also used in cosmetics.
Rice can be further understood, or categorized, in various ways including: country of origin (where the rice is grown), the subspecies group (japonica or indica); cultivation (conventional, hybrid, GMO); type (aromatic, non-aromatic); and grade (structural integrity, appearance, cooking time, and taste).
II. Rice Production & Trade
Most rice is grown in Asia and consumed locally, but rice is also grown on nearly every continent and consumed in various international cuisines.
III. Rice Types
Japonica rice is short or medium grain rice. Indica rice is long grain rice. Specialty rice types include: glutinous rice, aromatic rice (such as Jasmine rice or Basmati rice), and Arborio rice.
IV. Rice Ecosystems
Irrigated Rice : Spend more to make more. Irrigated rice consists of about 55% of global rice area and about 75% of global rice production - thanks to typically higher yields. However, the higher yields typically mean more purchased input costs. Irrigated rice areas are mostly concentrated in humid and sub humid subtropics and humid tropics. Rain-fed rice is mostly found in South and Southeast Asia.
Lowland Rice : Accounts for about 25% of global rice area and about 17% of global rice production. Rice is transplanted or direct-seeded into puddled soil on level to slight sloping-diked fields that are flooded for at least part of the cropping season – leaving the crop vulnerable to a lack of water control. Farmers grow traditional, photoperiod-sensitive varieties and rely more on labor than purchasing inputs.
Upland Rice : Consists of about 13% of global rice area and about 4% of global rice production due to extremely low yields. Upland rice is grown without standing water. Despite the low yields, this is the dominant rice culture in parts of Latin America and West Africa.
Flood-Prone Rice : Accounts for about 9% of global rice area and about 4% of world production due to low yields as a result of problematic soils and unpredictable droughts and floods. This includes both deep-water rice and floating rice. About 90% is farmed in South and Southeast Asia with the remaining 10% farmed in parts of West Africa and South America.
V. Rice Genetic Improvements
Conventional Breeding : “Conventional plant breeding has been going on for hundreds of years, and is still commonly used today. Early farmers discovered that some crop plants could be artificially mated or cross-pollinated to increase yields… While an extremely important tool, conventional plant breeding also has its limitations. First, breeding can only be done between two plants that can sexually mate with each other. This limits the new traits that can be added to those that already exist in a particular species. Second, when plants are crossed, many traits are transferred along with the trait/s of interest - including those traits that have undesirable effects on yield potential,” writes the ISAAA.
Hybrids : “Hybrid seeds can exceed conventional or open pollinated rice breeds in terms of yield, resistance to pests and diseases, and time to maturity. Hybrid seeds are developed by the hybridization or crossing of parent lines that are “pure lines” produced through inbreeding. Pure lines are plants that “breed true” or produce sexual offspring that closely resemble their parents. By crossing pure lines, a uniform population of F1 hybrid seed can be produced with predictable characteristics,” according to the ISAAA.
Because producing a pure line can take nearly a decade and must be constantly maintained, the seeds are more expensive than conventional varieties. In exchange for paying a higher price, the farmer gets a higher yield and better crop quality.
Genetically Modified Organisms (GMO) : Genetically modified rice has been genetically engineered. Their DNA has been altered to be more resistant to pests, pesticides, herbicides, or to have improved nutrients for instance. GMO rice has not becoming widely available for production or consumption. The best known GMO rice is Golden Rice, developed by a private company and then handed over to the International Rice Research Institute (IRRI) to further develop on a non-profit basis. GMO products remain controversial as some people see them as useful tools to feed a hungry planet while critics say GMOs are poorly managed and may pose a health risk.
VI. Rice Grades
Rice is inspected to determine a particular grain sample’s grading standard, which will determine its price on the market price. Inspectors may investigate rice grain size, integrity, color, odor, chalkiness, moisture, milling yield, and other factors.
Different rice producing nations have their own standards.The U.S. standards for rice can be found on the USDA website (http://www.gipsa.usda.gov/fgis/standards/ricestandards.pdf).
Milled rice may be sold as 100% whole, meaning all the grains are considered whole. Or, rice by 5% broken, 100% broken, or somewhere in between to indicate that the respective percentage of rice grains is broken. While some broken grains are a natural part of grain production and processing, higher percentage of broken grains could be due to compromised paddy quality (from poor seeds or weather for instance) or poor milling.